Chaules fbancis jenkins



Feb. 21; 1928. Re. 16,888

C. F. JENKINS ELECTROSCOPE PICTURE RECEPTION Original ile ept. 11, I922fi-ngl w Fig.1.

gnu e'ntoz [mums humusdemons Reissued Feb. 21,1928.

UNITED STATES onaanss mumcrs .nmxms, or wasnmorou, nxs'rnxc'r orCOLUMBIA, assmnon 'ro smtxms LABORATORIES, a coarona'rron or msrarc'r orconmm smc'rnosoorn rro'r'uan nncnr'rron.

w re so. 1,521,192, dated December so, 19%, Serial no. 587,523, filedSeptember 11, 1922. Application for reissue filed December 2a, 1920.Serial no. 157,825.

This invention relates to the transmission of pictures-by-radio, and hasfor its principal object means for interruptinga source of light at. thereceivin station, in order to 6 produce lights'and sha es and half-toneson the photographic surface upon which it impinges in the apparatus atthe'receijving station. r

Inthe' drawings herewith, Figure 1 is a 0 diagrammatic illustration ofthe device; and Figure 2 a detail'thereof, in both of which A is theprimary of an induction coil, and part of the receiving apparatus; B theseoonda% of the same coil; 0 an amplif ing a battery in the platecircuit 0 the E 'an induction coil, the primary of is in circuit withthe plate, and the tube i which high tension secondary in circuit withthe sriuare plates F and Between the two 29 ates, an extremely ligihtfilm member G is ung, on the su rt (Fig. 2 K is a source of light, alens for gat ering the diverging rays thereof and concentrating themonto the tar at G attached to the os-v 25 cillatingmember The lens Nisso located that one focus thereof is on the target G, and the otherfocus is on a light-sensitive film R fed forward by the roller S.

r The operation of the device is as follows: so When fluctuatingcurrentrepresenting the light values of "a picture is sent out from thebroadcasting station, it is picked up by the receivipf station, andthese fluctuatingcurrent vues, assing through the low side as primary oft e induction coil E, induces in the secondary of the transformer E ahigh potential of alternating character. The effect is to charge theplates F and F positive and negative, respectivel and alternately. 4cThe oscillatin member being grounded,

as, for examp e, on a water main, has butone sign,and, therefore,is-attracted toward the plate which at the moment has the op-Q positesign, and is repelled from the plate a which has the same sign. As thetwo'plates F and F constantly change their sign, it is obvious that themember G continually oscillates as it hangsfbet-ween'these two platesand in amplitude in proportion to the curso rent energy.

And as the light from the source K is directed onto the target G, whenthe latter is in neutral position the light will be cut of at thatpoint; but as the member G, and

its attached target G oscillates, the lightwill fiass onto the lens N,and thence to the film in greater or lesser amount, as the oscillationof the member is great or small. The. devices 0 crate, therefore, as alight-inter rupting s utter which permits li ht to pass in proportion tothe energy 0 the plate chargin -current. e

- It is o vious that with the specific arrange-. ment shown only asingle line varying in density will be recorded on the film, butit is tobe understood that the film and rotating drum are intended to representany suitable arrangement forproducing relative moves ment between. theprojected light and the light receiving surface, and it will be apparentto one skilled in the art that any one of several well known forms ofapparatus may beused to distribute the-light variations over thesurfacein proper order to reproduce the original picture or record."

. While my invention is primarily intended to be used in transmittinpictures, it is obvious that it maybe n light from said source, theoscillation of the light interce ting member resulting from the membering electrically char d and permitting varying amounts of, ght to'passit. g

2. In devices of the character described, a source. of light, twoelectro-statically charged members in alignment with said light and anoscillating-member so located there-between as to intercept light fromsaid source, said oscillating member sus nded between saidelectrostatically charge members and permitting varying amounts of lightto pass it. p

3. In devices of the character described, the combination'of a source oflight and an oscillating member in line with said light, and propelledbyan electrostatically charged plate and so located as to vary theamount 4. In devices 0 the class described, the

or photographiv cally recording any voltage-of'varying amcombination ofa source of light, a pair of p voltage; a sourceof Plates and minus, andso located as to varythe plates means for potentially char same and anoscillating member propelgd fiy said potentially charged alternatelyplus amount of the light passing said oscillating member.-

-'. In combination a source of varying light, a. light rec'eivi surface,and. electro-static means. controlle path of said light to ntercept thelight in by said source of volta and movable in the accordance with thevoltage variations and rmit light of va ing intensity to pass it orrecording modu ated values of light; 6. The combination of a source ofva ing voltage, a pair of spaced stationary p ates connected to theterminals of said source, a

movable member interposed between said plates andadapted to be moved byvariations in voltage of said source, a'source of light, a lightreceiving surface, and a light 7 till get carried movable ember andmovable in the path of said li ht tovariabl intercept said light forrecor lng modulate values. of light. 1 p v 7. The combination of asource of va ing voltage, a pair of spacedstationary p ates connected tothe terminals of said source, a movable member inte osed between saidplates'and adapted to 1 moved by variations in voltage ofsaid source, alight neceivin surface, means for directing a beam of liglit u )onsaidisurface, and a light target carrie V by said movable member andarranged to normally intercept said beam but movable in response tochanges in voltage to permit varying amounts of light to pass to saidsurface for recording modulated valv ues oilight.

In testimony whereof I aflix my signature.

CHARLES FRANCIS JENKINS.

